Recovery of sensory function after the implantation of oriented-collagen tube into the resected rat sciatic nerve

INTRODUCTION: In the present study, we examined the effect of oriented collagen tube (OCT) implantation on the recovery of sensory function of the resected rat sciatic nerve. MATERIALS AND METHODS: After a 10-mm long portion of the sciatic nerve of a rat was resected, an OCT was placed in the site of nerve defect. Recovery of the sensory function was evaluated using Von Frey test every 3 days after surgery. The regenerated tissue were histologically and ultrastructurally analyzed 2 and 4 weeks after the surgery. RESULTS: The sensory reflexes of the OCT group were restored to the level of that of the intact group after 15 days. Hematoxylin and eosin staining revealed the cross-linking between the proximal and distal stumps after 2 weeks. After 4 weeks, Luxol Fast Blue and immunohistochemical staining revealed the presence of myelin sheath from the proximal to distal region of the regenerated tissue and S100B staining confirmed the presence of Schwann cells. Interestingly, no myelin sheath was ultrastructurally observed around the regenerated axons at the central region after 2 weeks. CONCLUSIONS: These results suggest that OCTs facilitate the recovery of sensory function. Additionally, the non-myelinated axons contributed to the recovery of the sensory function.